Reclamation of discarded mineral-surface roofing.



UNITED sTATEs PATENT oEEIoE.

ROBERT L. FOWLER, 0F PERTH AMBOY, NEW JERSEY, ASSIGNOR TO THE BARBER ASPHALT PAVING COMPANY, 0F PHILADELPHIA, IEENNSYITANIA,` A CORPO- RATION OF WEST VIRGINIA.

Specification of Letters Patent.

Patented Jan. 14, 1919.

Application led November 1, 1918. Serial N o. 260,760.

To ZZ fre/wm, t may concern Be it known that I, ROBERT L. FOWLER, a citizen of the United States, residing in Perth Amboy, in the State of New J ersey, have invented certain new and useful Improvements in the Reclamation of Discarded il-Iineral-Surface Roofing, of which the folloaingis a specification, reference being had to thel accompanying drawings.

In the manufacture of prepared roofing with mineral or grit surface, a certain amount of .so-called mill ends, or other portions, are necessarily discarded by reason of imperfection. Usually, the imperfections are in the grit surface of the roofing and are due to irregularities or intermissions in the operation of applying the surfacing bitumen or the grit coating. In either case, the resulting imperfection of the final grit surface spoils the appearance of thc roofing, making it necessary to cut out such defective parts with corresponding loss to the manufacturers. The parts thus cut out must. either be, discarded as Waste or else sold at less than cost as seconds.

I have discovered that if the surfaces of shingles or sheet roongs, which are partially or impcrfectly coated and gritted, are exposed to a suitable temperature, therbituminous crust underlying the grit maybe softened and caused to flow together as a smooth coating and, in this condition, While the coating is warm and plastic, if a fresh supply of grit is distributed over the surface and pressed into it, it will adhere wherever the grit was hitherto lacking, and thus restore the sheet to its condition as first-class roofing material.

I have devised a simplel apparatus for carrying out this process which is illustratcd more or less diagrammatically in the accompanying drawing.

The apparatus consists of an endless conveyer l, of asbestos or other suitable noncombustiblc, insulating material. The con veyer is driven in the direction of the arrow under the propulsion of the supporting rolls 2 and 3, running at a slow, even rate of speed. The imperfect shingles 5, are successively laid or fed to the conveyer face upwards and advanced through an electric heating device comprehensively indicated at 5, binding posts 6, being provided for attachment of the line conductors 7 In practice, I have found that by subjecting the shingles to a temperature from 600 to 1000o F., for a period of two (2) to ve (5) minutes, the surface layer of bitumen .will become suiliciently soft and will flow sufficiently for the present purposes Without injury to the remaining parts of the structure or causing the bitumen to overrun the port-ions of the surface already covered with the grit.

After emerging from the heating device, the shingles are passed beneath a hopper 10, from which grit is caseaded as illustrated. Said hopper is provided with appropriate controlling means 11, whereby the rate of fiow of the grit may be accurately regulated.

After this, the shingles are deliver beneath a compression roll 12, which 'i erates with the driving roller 3, lof the con? veyer. By the latter action, thegrit is firmly pressed into the fused bare spots of the shingles with the result that the surface becomes uniformly coated and the product saleable as a. first-class article.

The sheets are discharged from the machine, under the guidance of an inclined screen'15. The surplus grit drops through the latter and is collected in a receiving trough from Which it-may from time to time be returned to the hopper 10.

Having thus described my invention, I claim- The process of restoring imperfectly gritted roofing material which consists in subiec-ting the imperfect surface to heat sufficient to soften and distribute the, bituminous coating; applying additional grit. thereto while still soft; and pressing the grit into the softened bituminous surface.

In testimony whereof I 'have hereunto signed my name at Philadelphia, Pennsylvania, this twenty-first day of October, 1918.

ROBERT L. FOWLER. Witnesses:

WILLIAM A.. ODONNELL, JOSEPH G. SoHUoK. 

